Sound translating device



Feb. 18, 1941. H G. M. GIANNINI 2,232,380

SOUND TRANSLATING DEVICE Filed Jan. 5, 1938 2 Sheets-Sheet 1 INVENTOR I GABR/EL M G/ANN/N/ F b. 18, 1941. G M GANNM 2,232,380

souma TRANSLATING DEVICE Filed Jan. 5, 1938 2 Sheets-Sheet 2 INVENTOR ABR/EL M G/ NN/NI Patented Feb. 18, 1941 UNITED STATES SOUND TRANSLATING DEVICE Gabriel M. Giannini, Great Neck, N. Y., assignor, by mesne assignments, to Associated Electric Laboratories. Inc., Chicago, Ill., a corporation of Delaware Application January 5, 1938, Serial No. 183,429 Claims. (Cl. 179-179) This invention relates to a sound energy translating device, such as a microphone or loudspeaker and more particularly to the housing which provides support and acoustical environ- 5 ment to the energy translating device.

In such devices of conventional design, and especially with microphones, certain inconveniences and limitations as to use have been accepted, important among which are that they are easily injured by shock, that they are adversely effected by moisture and that they require ordinarily a rigid or semi-rigid adjustable stand which may be more cumbersome and expensive to handle than the microphone itself.

It is an object of the present invention to eliminate such inconveniences and limitations and to provide a sound energy translating unit which is rugged, compact and easily handled under all circumstances and which will operate withput disadvantage under any ordinary weather conditions or other conditions of use which would seriously affect or render totally inoperative the energy translating devices which are now in common use.

5 Another object of the invention is to provide means for suspending the microphone which is easily adjustable, and readily adapted to different locations.

Another object of the device is to provide a at, housing for the energy translating unit which serves at-once to provide an advantageous acoustical environment and to protect the delicate parts of the mechanism against shock when the device is roughly handled.

35 In the accompanying drawings 1 have shown a preferred embodiment of my invention. These drawings are not to be taken as exhaustive or limiting of the invention but are shown merely with a view to explaining and illustrating the invention so that others skilled in the art may apply it to practical use in numerous forms and with various modifications each as may be best adapted for any particular use.

Fig. 1 is a view in longitudinal section of a 5 sound energy translating unit embodying my invention;

Fig. 2 is a view in end elevation of the same embodiment; 1

Figs. 3 and 4 are views in side elevation on a 50 reduced scale of the same embodiment showing difierent positions of use; and

Fig. 5 is a view in perspective showing another position of use.

As shown in Fig. l, the housing is formed of 66 soit vulcanized rubber made in two parts II and II cemented together as shown at l2. The part it is formed with an opening or openings i3 which communicates with the chamber 14 over the diaphragm iii of a moving coil type microphone or speaker unit it which may con- 5 sist, for example, of a substantially closed cy1indrical magnet having a central post as one pole and as its other pole an annular plate surrounding the upper end of the central post and attached to the cylindrical shell portion of the w magnet. A gap remains between the poles within which moved the coil attached to the diaphragm. This construction is already known,

e. g., from my application Serial No. 99,019, filed September 2, i936; and, therefore, need 15 not be further described nor shown in detail in the drawings.

This unit is engaged in a recess il within the housing i0--il and is clamped therein by the member II, which engages against the periphery 20 of the unit i8 as clearly shown. In the case illustrated, the recess II extends beyond the unit it and the resulting chamber may be used as an acoustical matching chamber to improve the desired acoustical response of the device, and in this space also may be mounted a matching transformer II.

A thin flexible membrane 20 is secured to the inside of the housing ii over the openings i3,

e. g., by cementing at it. This membrane is advantageously a very thin rubber membrane and is made in the form shown so that it is unstretched and in its relaxed position will avoid acoustical effects which would result if a stretched membrane were used for this purpose.

The main body of the housing i0ii is. made in streamline form as described and claimed in my copending application, Serial No. 99,019, filed September 2, 1936. In this case, however, I have provided at least three fins 22 which in the case illustrated are radial and with two of the fins on opposite sides of the diameter through the first, e. g., at 120' 0r 90 spacing. These flns have their bottoms lying in a plane substantially perpendicular to the axis of the hous- 5 ing and at least two fins are pierced near their corners for the reception of a supporting cord or hooks.

In Fig. 3, I have shown the device mounted in a substantially horizontal position on a vertically stretched cord 24. For this purpose the cord may be tied between any convenient supports preferably after threading through opposite periorations 23. With the cord drawn taut as shown the microphone may be adjusted to N any position by sliding along the cord; and its own weight, tending to twist it on the cord, holds it in any given position by crowding t'ne cord against opposite sides of the opposite perforations. If only one point of support is conveniently available the same system may be used by hanging a heavier weight on the cord 24 below this device so that the cord is held taut. Thus by the simple use of a cord and this simple form of microphone it may be adjustably "upported in almost any location.

If it is not convenient to hang the microphone in the horizontal position as shown in Fig. 3, a cord 24a may be stretched horizontally between supports and the microphone similarly hung as shown in Fig. 4. A supplemental cord 25 may be tied or weighted to steady or adjust the position of the microphone on the cord a. If it is desired to use the microphone on a table, or rostrum, or any other horizontal surface, the fins 22 serve as legs for supporting the microphone upright in the position shown in Fig. 5.

It will be understood from what has been said above that the device as shown and described is convenient for use in many locations where ordinary microphones mounted on stands would be extremely cumbersome or unsuitable, that it can be carried from place to place easily; that the soft rubber housing is not only itself unbreakable but serves to protect the delicate parts of the translating device against injury from shock to which it may be subjected in handling, and that the housing being completely enclosed and sealed with waterproof materials is adapted to protect the translating device against imury and any adverse effects from moisture and even with complete submersion in water.

It should be understood, however, that many of the details of the device as shown and described above can be varied without departing from my invention. Thus, although I have shown and described a translating device of the dynamic or moving coil type other types of microphones or speaker units could be used instead; and although 1 have particularly referred to the use of soft rubber as the material both for the housing part Hl-|| and for the membrane 20 other materials can be used for this purpose. If the greatest protection against shock is desired the parts II and H are advantageously made of a sponge rubber composition, where as if this is not considered important they may be made of more rigid materials such as Celluloid, hard rubber, wood or even Bakelite. There is, however, great advantage in the use of the softer and more resilient materials such as soft vulcanized rubber or the various recently developed synthetic materials of similar properties. For the sealing membrane 20 other more or less impervious or semi-permeable films may be used instead of rubber, as for example, cellulosic films, e. g., of the type commonly known under the trade name Cellophane, or organic membranes such as are used for sausage casings and other thin membranes. In general, however, such membranes will be found less impermeable to moisture than the rubber membrane and for that and other reasons rubber is of advantage.

What I claim is:

1. An acoustic device comprising a streamlined casing having a translating device mounted within said casing, openings in said casing for the passage of sound waves, and means comprising fin-shaped members for supporting said casing in an upright position, said fins having means for supporting the casing by means of cords.

2. An acoustic device comprising a casing having a sound translating unit mounted within said casing, a plurality of openings in the front end of said casing for the passage of sound waves to or from said sound translating unit, means formed in said casing in the end opposite said openings for supporting the casing in an upright position on a flat surface and for suspending the unit by cords.

3. An acoustic device comprising a combined microphone-loudspeaker unit, a casing for supporting said unit, a plurality of sound openings in the front end of said casing communicating with said unit for the passage of all sound waves, three fins formed in the rear end of said casing forming a tripod for supporting the casing in an upright position on a'. relatively flat surface, said casing and fins formed of vulcanized rubber to reduce the possibility of vibrations transmitted through said surface from interfering with the reproducing characteristics of said unit.

4. A sound translating device comprising a streamlined shaped housing of shock absorbing waterproof material having an opening in its nose for the free passage of sound energy, a sound translating unit enclosed in said housing, a. thin flexible, not-elastic diaphragm being loosely placed over said opening and having its edges securely fastened and sealed into said device, said housing having longitudinal fins which terminate in a plane perpendicular to an axis through the device, and on which the device may be stood.

5. A sound translating device comprising a streamlined shaped housing of shock absorbing waterproof material having an opening in its nose for the free passage of sound energy, a sound translating unit enclosed in said housing, a thin flexible, non-elastic diaphragm being loosely placed over said opening and having its edges securely fastened and sealed into said device, and said housing terminating in fins and opposite fins having holes through which to pass a supporting string.

GABRIEL M. GIANNINI. 

